It brought celebrity TV host James Corden to tears, and made singer Christina Perri tweet that her ‘heart is full’. The viral video that has people damp-eyed around the world is a ‘carpool karaoke’ style lip sync video, created for World Down Syndrome Day (March 21).

Titled ’50 Mums | 50 Kids | 1 Extra Chromosome’, the video was created by mums from the Facebook group ‘Designer Genes’, who all have a child with Down Syndrome. It was inspired by another Youtube video made by a mum-and-daughter pair from a UK Youtube Channel called Singing Hands, which teaches Makaton sign language used by many children with Down Syndrome and their parents.

Christina Perri’s song 1000 Years, made famous by the Twilight movies, is a favourite song for 18-year-old Ella, who features in the original video.